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1.
Phys Rev Lett ; 131(20): 207401, 2023 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-38039484

RESUMO

The emergence of collective behaviors in networks of dynamical units in pairwise interaction has been explained as the effect of diffusive coupling. How does the presence of higher-order interaction impact the onset of spontaneous or induced synchronous behavior? Inspired by actuation and measurement constraints typical of physical and engineered systems, we propose a diffusion mechanism over hypergraphs that explains the onset of synchronization through a clarifying analogy with signed graphs. Our findings are mathematically backed by general conditions for convergence to the synchronous state.

2.
Echocardiography ; 35(4): 506-519, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29600543

RESUMO

The use of conventional echocardiography in the intensive care unit (ICU) is today established to assess left and right ventricular systolic function, for preload determination and procedural guidance. Next step in ICU echocardiography could be the use of novel ultrasound techniques such as strain echocardiography to assist in the management of patients with acute coronary syndrome, heart failure, or pulmonary embolism. This review has gathered the available evidence supporting the incremental value of strain in the diagnostic workup of cardiac diseases treated in ICU.


Assuntos
Cuidados Críticos/métodos , Ecocardiografia/métodos , Cardiopatias/diagnóstico por imagem , Unidades de Terapia Intensiva , Coração/diagnóstico por imagem , Humanos
3.
Echocardiography ; 34(2): 240-249, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28070903

RESUMO

BACKGROUND: Mucopolysaccharidoses (MPS) are inherited lysosomal storage disorders caused by deficiency of required glycosaminoglycans breakdown enzymes, inducing cardiac involvement. Little is known about myocardial deformation involvement in MPS. Our aim was to assess biventricular structure and function in asymptomatic children with MPS using standard echo Doppler and 2D speckle tracking (STE). METHODS: Fifteen MPS children (one type I, six type II, three type III A, one III B, three IV A, one VI), asymptomatic for cardiac symptoms, and 15 age and sex-matched healthy controls underwent echo Doppler and STE. Left ventricular (LV) wall thicknesses, diameters, and mass were normalized by z-score. LV global longitudinal strain (GLS), global circumferential strain (GCS), global radial strain (GRS) at papillary muscles, LV twisting, and right ventricular (RV) GLS were measured. RESULTS: The two groups were comparable for body mass index, heart rate, and blood pressure. LV mass index and relative wall thickness were higher in MPS. Ejection fraction (EF), and s' velocity did not differ between the two groups. E/A ratio was lower and E/e' higher in MPS. Tricuspid annular plane systolic excursion, RV s' and e' were lower in MPS. LV GLS did not differ between the two groups, but GCS (P=.014), GRS (P=.023), twisting (P=.012), and RV GLS (P<.001) were lower in the MPS group. CONCLUSIONS: LV strain abnormalities are detectable in MPS pediatric patients, independently of MPS type, when EF is still normal. RV GLS is also involved consensually with TAPSE reduction. STE can be useful for detection of subclinical myocardial damage in MPS.


Assuntos
Ecocardiografia , Mucopolissacaridoses/complicações , Disfunção Ventricular/complicações , Disfunção Ventricular/diagnóstico por imagem , Criança , Ecocardiografia Doppler , Feminino , Ventrículos do Coração/diagnóstico por imagem , Ventrículos do Coração/fisiopatologia , Humanos , Masculino , Mucopolissacaridoses/fisiopatologia , Reprodutibilidade dos Testes
4.
Echocardiography ; 32(6): 890-5, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25250513

RESUMO

Type I Gaucher disease (GD1) is an autosomal recessive lysosomal storage disease characterized by multiorgan damage. Left ventricular (LV) involvement has been rarely reported. Accordingly, the aim of the study was to evaluate LV geometry and function in a series of patients with GD1. Eighteen patients with GD1, 18 age- and sex-matched normal controls, and 18 age- and sex-matched hypertensive patients (HTN) were compared by standard echo Doppler examination. LV mass index, relative wall thickness and ejection fraction, transmitral E/A ratio, E velocity deceleration time (DT), atrial filling fraction (AFF = time-velocity integral of A velocity/time-velocity integral of total diastole × 100), E/e' ratio, and left atrial volume index were determined. Nine GD1 patients also exhibited arterial hypertension. The intergroup difference of LV mass index and relative wall thickness was not significant. Transmitral E/A ratio was lower in HTN than in normal controls and GD1 (P < 0.05). GD1 exhibited longer DT than NC and HTN (P = 0.009). AFF was higher in GD1 and HTN compared to NC (P = 0.034). After adjustment for heart rate, GD1 was associated with longer DT (P < 0.001) and greater AFF (P = 0.036), while HTN was associated only with AFF (P = 0.013). No interaction was found between GD1 and HTN. In conclusion, GD1 is associated with subclinical LV diastolic dysfunction, which is independent of the coexistence of arterial hypertension. Subclinical LV impaired relaxation in the context of myocardial infiltrative damage could be the mechanism underlying these alterations.


Assuntos
Ecocardiografia Doppler/métodos , Doença de Gaucher/complicações , Doença de Gaucher/diagnóstico por imagem , Hipertensão/diagnóstico , Disfunção Ventricular Esquerda/diagnóstico por imagem , Disfunção Ventricular Esquerda/etiologia , Diagnóstico Diferencial , Feminino , Humanos , Hipertensão/etiologia , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
5.
Eur J Nucl Med Mol Imaging ; 39(7): 1199-206, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22526959

RESUMO

PURPOSE: We assessed the impact of type 2 diabetes, in the presence of other major cardiovascular risk factors, on coronary microvascular function and myocardial perfusion in patients without obstructive coronary artery disease (CAD). METHODS: In this prospective study, 23 patients with type 2 diabetes and 26 nondiabetic patients matched for age, sex and other cardiovascular risk factors underwent a cold pressure test (CPT) and dipyridamole transthoracic echocardiography to determine their coronary flow (CF) ratio. Within 2 weeks, all diabetic patients also underwent dipyridamole-rest myocardial perfusion single-photon emission (MPS) CT. None of the patients with or without diabetes had significant CAD on invasive coronary angiography. RESULTS: The CPT-CF ratio was significantly lower in diabetic patients than in nondiabetic patients (1.46 ± 0.26 vs. 1.71 ± 0.32, p = 0.006) and was correlated significantly with fasting glycaemia (r = -0.35, p = 0.01), but not with glycated haemoglobin. The dipyridamole-CF ratio was also lower in diabetic patients than in nondiabetic patients (2.38 ± 0.74 vs. 2.75 ± 0.49, p = 0.04). On MPS imaging, 5 diabetic patients (22%) had stress-induced ischaemia and the remaining 18 (78%) had normal myocardial perfusion. The dipyridamole-CF ratio was not different in patients with and without reversible defects (2.3 ± 1.1 vs. 2.4 ± 0.6, p = 0.97). CONCLUSION: Coronary microvascular function is impaired in type 2 diabetic patients without significant CAD, compared to nondiabetic patients with similar other cardiovascular risk factors. In the majority of diabetic patients, microvascular dysfunction is associated with normal myocardial perfusion.


Assuntos
Doença da Artéria Coronariana/fisiopatologia , Doença das Coronárias/fisiopatologia , Diabetes Mellitus Tipo 2/fisiopatologia , Angiopatias Diabéticas/fisiopatologia , Isquemia Miocárdica/fisiopatologia , Idoso , Estudos de Casos e Controles , Angiografia Coronária , Doença da Artéria Coronariana/diagnóstico por imagem , Doença da Artéria Coronariana/patologia , Circulação Coronária/fisiologia , Doença das Coronárias/diagnóstico por imagem , Doença das Coronárias/etiologia , Diabetes Mellitus Tipo 2/patologia , Dipiridamol , Ecocardiografia Doppler , Feminino , Humanos , Masculino , Microvasos/diagnóstico por imagem , Microvasos/patologia , Pessoa de Meia-Idade , Isquemia Miocárdica/diagnóstico por imagem , Isquemia Miocárdica/etiologia , Imagem de Perfusão do Miocárdio/métodos , Estudos Prospectivos , Tecnécio Tc 99m Sestamibi , Tomografia Computadorizada de Emissão de Fóton Único/métodos
6.
Monaldi Arch Chest Dis ; 78(1): 34-9, 2012 Mar.
Artigo em Italiano | MEDLINE | ID: mdl-22928402

RESUMO

AIM: to evaluate endothelial function (EF) in diabetic and non-diabetic patients without CAD by peripheral artery tonometry (PAT) technique. METHODS: a cohort of 94 patients (55 men and 39 postmenopausal women; mean age 63 +/- 9 years) undergoing coronary angiography was divided into 2 groups: 58 patients with DM and (group 1) and 36 patients without DM. Endothelial dysfunction (ED) was assessed by digital pulse amplitude, using a fingertip peripheral arterial tonometry (PAT). As a measure of ED, reactive hyperemia index (RHI) was calculated as the ratio of the digital pulse volume during reactive hyperemia following 5 min ischemia and its basal value. RESULTS: prevalence of cardiovascular risk factors was similar between the two groups. RHI values were significantly lower in diabetic patients compared to non-diabetics (1.72 +/- 0.34 vs 2.00 +/- 0.44; p < 0.005) and they correlated with levels of glycosylated hemoglobin (p = 0.05; r = -0.266). CONCLUSION: despite similar level of other risk factors, EF was much more impaired in diabetic patients than in non-diabetics. These evidences further support the impact of DM on cardiovascular risk.


Assuntos
Diabetes Mellitus Tipo 2/fisiopatologia , Endotélio Vascular/fisiopatologia , Vasos Coronários , Feminino , Humanos , Masculino , Manometria , Pessoa de Meia-Idade
7.
Sci Rep ; 11(1): 6977, 2021 03 26.
Artigo em Inglês | MEDLINE | ID: mdl-33772037

RESUMO

Recently, it has been suggested that network temporality can be exploited to substantially reduce the energy required to control complex networks. This somewhat counterintuitive finding was explained through an evocative example of the advantage of temporal networks: when navigating a sailboat, we raise the sails when the wind helps us while lowering them when it works against us. Unfortunately, controlling complex networks inherits a further analogy with navigating a sailboat: having to face the inherent uncertainty of future winds. We rarely, if ever, have deterministic knowledge of the evolution of the network we want to control. Here, our challenge is to exploit the potential advantages of temporality when only a probabilistic description of the future is available. We prove that, in this more realistic setting, exploiting temporality is no more a panacea for network control, but rather an asset of a wider toolbox made available by the scientific community. One that can indeed turn out useful, provided that the temporality of the network structure matches the intrinsic time scales of the nodes we want to control.

8.
Nat Commun ; 11(1): 5106, 2020 10 09.
Artigo em Inglês | MEDLINE | ID: mdl-33037190

RESUMO

The COVID-19 epidemic hit Italy particularly hard, yielding the implementation of strict national lockdown rules. Previous modelling studies at the national level overlooked the fact that Italy is divided into administrative regions which can independently oversee their own share of the Italian National Health Service. Here, we show that heterogeneity between regions is essential to understand the spread of the epidemic and to design effective strategies to control the disease. We model Italy as a network of regions and parameterize the model of each region on real data spanning over two months from the initial outbreak. We confirm the effectiveness at the regional level of the national lockdown strategy and propose coordinated regional interventions to prevent future national lockdowns, while avoiding saturation of the regional health systems and mitigating impact on costs. Our study and methodology can be easily extended to other levels of granularity to support policy- and decision-makers.


Assuntos
Controle de Doenças Transmissíveis/métodos , Infecções por Coronavirus/prevenção & controle , Pandemias/prevenção & controle , Pneumonia Viral/prevenção & controle , Regionalização da Saúde/métodos , Betacoronavirus , COVID-19 , Simulação por Computador , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/transmissão , Humanos , Itália/epidemiologia , Modelos Teóricos , Pneumonia Viral/epidemiologia , Pneumonia Viral/transmissão , SARS-CoV-2
9.
J Hypertens ; 36(8): 1697-1704, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29570513

RESUMO

BACKGROUND: Elevated left ventricular (LV) mass/end-diastolic volume ratio (LVM/EDV) has been associated with higher evidence of myocardial fibrosis and dysfunction in hypertensive patients by cardiac magnetic resonance, a technique with limited availability. OBJECTIVES: We investigated the ability of three-dimensional (3D) echocardiography in identifying a phenotype of LV concentric geometry according to LVM/EDV ratio, possibly detecting early myocardial damage in native-hypertensive patients. METHODS: One hundred and twenty-eight native-hypertensive patients underwent 2D and 3D-echocardiography. The population was divided into two groups, according to cut-off point values of 3D-LVM/EDV ratio corresponding to its upper 95% confidence interval in a population of 90 healthy normotensive individuals: LVM/EDV ratio cut-off was 1.22 in men and 1.23 in women. RESULTS: An increased 3D-LVM/EDV ratio identified a higher rate of LV concentric geometry in comparison with 2D-derived relative wall thickness (37 versus 24%, P = 0.03). Patients with LVM/EDV ratio of 1.22 or more in men and 1.23 or more in women were significantly older, had smaller 3D-LV end-diastolic and end-systolic volumes and higher LV mass index, without difference in ejection fraction. 3D-stroke volume (P < 0.0001) was lower in patients with elevated LVM/EDV ratio. By a multilinear regression analysis, after adjusting for sex, age, heart rate, mean blood pressure and BMI, stroke volume was independently and negatively associated to LVM/EDV ratio (ß = -0.55, P < 0.0001). CONCLUSION: In native hypertensive patients, 3D-echo-derived LVM/EDV ratio identifies a higher prevalence of LV concentric geometry than 2D-relative wall thickness. Stroke volume is independently and negatively associated with LVM/EDV ratio and its reduction represents an early marker of myocardial dysfunction in hypertensives with LV concentric geometry.


Assuntos
Ecocardiografia Tridimensional , Hipertensão/fisiopatologia , Hipertrofia Ventricular Esquerda/diagnóstico por imagem , Hipertrofia Ventricular Esquerda/fisiopatologia , Volume Sistólico , Adulto , Pressão Sanguínea , Diástole , Feminino , Humanos , Hipertensão/complicações , Hipertrofia Ventricular Esquerda/etiologia , Masculino , Pessoa de Meia-Idade , Adulto Jovem
10.
Eur Heart J Cardiovasc Imaging ; 19(12): 1390-1396, 2018 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-29211878

RESUMO

Aims: Recent advancements in echocardiographic technology allow to analyse myocardial strain in multiple layers. Little is known about the impact of age on layer-specific longitudinal strain in healthy subjects. The aim of this study was to analyse the influence of age on multilayer longitudinal strain and establish normal reference values of layer-specific strain according to age decades in a healthy population referring to our echo laboratory using 2D speckle-tracking echocardiography with layer-specific software. Methods and results: Two-hundred sixty-six healthy, consecutive subjects (mean age = 39.2 ± 17.5 years, women/men = 137/129), free of cardiovascular risk factors, were enrolled. Subjects were divided according to six age decades: 10-19, 20-29, 30-39, 40-49, 50-59, >60 years. All subjects underwent a complete echo Doppler examination including quantitation of 2D global longitudinal strain (GLS). Subendocardial longitudinal strain (LSsubendo), subepicardial longitudinal strain (LSsubepi), and strain gradient (LSsubendo - LSsubepi) were also determined. GLS (P < 0.001), LSsubendo, and LSsubepi (both P < 0.0001) were all progressively reduced with increasing age decades, but post hoc intra-group analyses demonstrated that the decline of GLS, LSsubendo, and LSsubepi was significant in the decades 50-60 and ≥60 years. In separate multiple linear regression analyses, the effect of age on GLS, LSsubendo, and LSsubepi remained significant even after adjusting for clinical and echocardiographic confounders. Strain gradient remained unchanged in age decades. Conclusion: Ageing shows an independent effect on GLS, LSsubendo, and, particularly on, LSsubepi. Our data also provide normal reference values of layer-specific longitudinal strain for age decades.


Assuntos
Ecocardiografia/métodos , Interpretação de Imagem Assistida por Computador , Volume Sistólico/fisiologia , Função Ventricular Esquerda/fisiologia , Adulto , Fatores Etários , Estudos de Coortes , Feminino , Voluntários Saudáveis , Humanos , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Estudos Prospectivos , Valores de Referência
11.
Eur Heart J Cardiovasc Imaging ; 19(3): 245-252, 2018 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-29474699

RESUMO

The European Society of Cardiology (ESC) guidelines for management of atrial fibrillation (AF) recommend the use of CHA2DS2VASc risk score for assessment of thromboembolic (TE) risk, whereas the stratification of bleeding risk should be obtained by HAS-Bleed to balance the most appropriate anticoagulation (OAC) therapy. However, men with CHA2DS2VASc score = 1 and women with CHA2DS2VASc = 2, who are at intermediate TE risk, represent a grey zone where guidelines do not provide a definite OAC indication. Accordingly, implementation of risk stratification with echocardiography could be extremely useful. Both prospective and cross-sectional studies on transthoracic echocardiography (TTE) prediction of TE events and studies utilizing transoesophageal echocardiographic parameters as surrogate markers of TE events makes sustainable the hypothesis that echocardiography could improve TE prediction in non-valvular AF. Moreover, considering the close association of AF and stroke, all echo-Doppler parameters that have shown to predict AF onset and recurrence could be useful also to predict TE events in this clinical setting. Accordingly, EACVI AFib Echo Europe Registry has been designed as an observational, cross-sectional study, with the aim of evaluating: (i) left atrial (LA) size and function together with left ventricular geometry, systolic and diastolic functions in paroxysmal, persistent, and permanent AF; (ii) relationships of structural/functional parameters with clinical TE and bleeding risk profile. By the AFib Echo Europe Registry, we expect to collect data on echocardiographic phenotype of patients with AF. The large data set accumulated will be useful to test the level of agreement of different echocardiographic measurements with the available risk scores.


Assuntos
Fibrilação Atrial/diagnóstico por imagem , Fibrilação Atrial/patologia , Ecocardiografia/métodos , Hemorragia/etiologia , Guias de Prática Clínica como Assunto , Sistema de Registros , Fibrilação Atrial/complicações , Cardiologia/normas , Estudos Transversais , Feminino , Hemorragia/diagnóstico por imagem , Hemorragia/terapia , Humanos , Masculino , Valor Preditivo dos Testes , Estudos Prospectivos , Medição de Risco , Sensibilidade e Especificidade , Sociedades Médicas , Tromboembolia/diagnóstico por imagem , Tromboembolia/etiologia , Tromboembolia/terapia
12.
PLoS One ; 12(2): e0171891, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28196144

RESUMO

To overcome the limitations of neoclassical economics, researchers have leveraged tools of statistical physics to build novel theories. The idea was to elucidate the macroscopic features of financial markets from the interaction of its microscopic constituents, the investors. In this framework, the model of the financial agents has been kept separate from that of their interaction. Here, instead, we explore the possibility of letting the interaction topology emerge from the model of the agents' behavior. Then, we investigate how the emerging cobweb of relationship affects the overall market dynamics. To this aim, we leverage tools from complex systems analysis and nonlinear dynamics, and model the network of mutual influence as the output of a dynamical system describing the edge evolution. In this work, the driver of the link evolution is the relative reputation between possibly coupled agents. The reputation is built differently depending on the extent of rationality of the investors. The continuous edge activation or deactivation induces the emergence of leaders and of peculiar network structures, typical of real influence networks. The subsequent impact on the market dynamics is investigated through extensive numerical simulations in selected scenarios populated by partially rational investors.


Assuntos
Algoritmos , Administração Financeira/economia , Investimentos em Saúde/economia , Marketing/economia , Modelos Econômicos , Simulação por Computador , Administração Financeira/métodos , Humanos , Marketing/métodos , Dinâmica não Linear
13.
Comput Soc Netw ; 4(1): 12, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29266119

RESUMO

In this paper, we model the problem of influencing the opinions of groups of individuals as a containment control problem, as in many practical scenarios, the control goal is not full consensus among all the individual opinions, but rather their containment in a certain range, determined by a set of leaders. As in classical bounded confidence models, we consider individuals affected by the confirmation bias, thus tending to influence and to be influenced only if their opinions are sufficiently close. However, here we assume that the confidence level, modeled as a proximity threshold, is not constant and uniform across the individuals, as it depends on their opinions. Specifically, in an extremist society, the most radical agents (i.e., those with the most extreme opinions) have a higher appeal and are capable of influencing nodes with very diverse opinions. The opposite happens in a moderate society, where the more connected (i.e., influential) nodes are those with an average opinion. In three artificial societies, characterized by different levels of extremism, we test through extensive simulations the effectiveness of three alternative containment strategies, where leaders have to select the set of followers they try to directly influence. We found that, when the network size is small, a stochastic time-varying pinning strategy that does not rely on information on the network topology proves to be more effective than static strategies where this information is leveraged, while the opposite happens for large networks where the relevance of the topological information is prevalent.

14.
Int J Cardiol ; 243: 544-549, 2017 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-28526545

RESUMO

BACKGROUND: Little is known on right ventricular (RV) involvement in obstructive sleep apnoea (OSA). This study aimed at evaluating early RV dysfunction by standard and advanced echocardiography in OSA. METHODS: Fifty-nine OSA patients without heart failure and 29 age-matched controls underwent standard, speckle tracking and real time 3D echocardiography of right ventricle. OSA patients performed lung function tests and overnight cardio-respiratory monitoring with evaluation of apnea-hypopnea index (AHI). RESULTS: OSA had significantly higher body mass index and systolic blood pressure (BP) than controls. RV diameters and systolic pulmonary arterial pressure (sPAP) were significantly higher in OSA, in presence of comparable tricuspid annular plane systolic excursion (TAPSE). OSA showed marginally lower RV global longitudinal strain (GLS) (p<0.05) and RV lateral wall strain (RV LLS) (p=0.04). Three-dimensional RV ejection fraction did not differ between the two groups. By stratifying patients according to sPAP, 18 OSA patients with sPAP≥30mmHg had lower TAPSE (p<0.05), RV GLS and RV LLS (both p<0.001) than 37 patients with normal sPAP. By separate multivariate analyses, RV GLS and RV LLS were independently associated with sPAP (both p<0.0001), AHI (p=0.035 and p=0.015 respectively) and BMI (p<0.05 and p=0.034) but not with age and systolic BP in OSA. CONCLUSIONS: A subclinical RV dysfunction is detectable by speckle tracking in OSA. The impairment of RV GLS and RV LLS is more prominent than that of TAPSE and is evident when RVEF is still normal. GLS is independently associated with sPAP and OSA severity.


Assuntos
Ecocardiografia Doppler/métodos , Ecocardiografia Tridimensional/métodos , Apneia Obstrutiva do Sono/diagnóstico por imagem , Disfunção Ventricular Direita/diagnóstico por imagem , Função Ventricular Direita/fisiologia , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Apneia Obstrutiva do Sono/epidemiologia , Apneia Obstrutiva do Sono/fisiopatologia , Disfunção Ventricular Direita/epidemiologia , Disfunção Ventricular Direita/fisiopatologia
15.
Eur Heart J Cardiovasc Imaging ; 18(5): 549-555, 2017 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-27325809

RESUMO

AIMS: The determinants of systolic function in the performing heart are not completely understood. Aim of the study was to assess the contributors of left ventricular (LV) strain components, using 3D speckle tracking echocardiography (STE) in endurance athletes. METHODS AND RESULTS: A total of 36 top-level male endurance athletes (AT) and 36 age-matched sedentary normal controls (NC) underwent standard and real-time 3D echocardiography. Global longitudinal strain (GLS), global circumferential strain (GCS), global area strain (GAS), and global radial strain (GRS) were assessed using 3D STE. AT had significantly higher GLS (-22.1 ± 4.4 vs. -18.4 ± 3.5%; P < 0.0001), GCS (-17.9 ± 2.4 vs. -16.0 ± 3.2; P = 0.006), and GAS (-35.5 ± 6.7 vs. -30.2 ± 4.9; P < 0.0001), while GRS did not differ significantly with NC. At separate multiple linear regression analyses, heart rate emerged as independent predictor of GLS (ß = -0.37, P < 0.002), GCS (ß = -0.32, P = 0.007), GAS (ß = -0.37, P < 0.001), and GRS (ß = -0.29, P = 0.019); LV mass was independently associated with GLS (ß = 0.34, P = 0.009) and GAS (ß = 0.41, P < 0.001) but not with GCS and GRS, while diastolic blood pressure predicted GCS (ß = -0.46, P < 0.0001), GAS (ß = -0.28; P = 0.006), and GRS (ß = -0.42, P < 0.001). No independent correlation emerged for body surface area and stroke volume. By replacing LV mass with end-diastolic volume, the latter showed independent association with GCS (ß = -0.65, P = 0.028) and with GRS (ß = -0.60, P < 0.05). CONCLUSION: AT have an increased myocardial function at rest when compared with NC, this being elicited mainly by subendocardial and mid-wall fibres. Sinus bradycardia, LV mass, and afterload are independent determinants of supernormal myocardial deformation at rest.


Assuntos
Atletas , Ecocardiografia Tridimensional/métodos , Processamento de Imagem Assistida por Computador , Resistência Física/fisiologia , Volume Sistólico/fisiologia , Função Ventricular Esquerda/fisiologia , Adulto , Estudos de Casos e Controles , Humanos , Modelos Lineares , Masculino , Análise Multivariada , Contração Miocárdica/fisiologia , Valores de Referência , Comportamento Sedentário , Adulto Jovem
16.
J Am Heart Assoc ; 6(7)2017 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-28663250

RESUMO

BACKGROUND: The aim of our study was to evaluate the relationship of pulse pressure (PP), a raw index of arterial stiffness, with noninvasively determined coronary flow reserve (CFR) and its components, in patients with angiographically normal epicardial coronary arteries. METHODS AND RESULTS: The study population included 398 patients without angiographic evidence of coronary stenosis, who underwent high-dose dipyridamole stress echocardiography with transthoracic-derived CFR evaluation on the left anterior descending artery. CFR was calculated as the ratio between high-dose dipyridamole and resting coronary diastolic peak velocities. Patients were divided into 2 groups: the first group included the first and second PP tertiles (n=298, PP ≤60 mm Hg) and the second group included the highest PP tertile (n=100, PP >60 mm Hg). Mean blood pressure, systolic blood pressure (both P<0.0001), age (P<0.002), and left ventricular mass index (P=0.013) were higher in the highest PP tertile, which also showed higher resting coronary flow velocity (31.6±9.6 cm/s versus 27.7±6.4 cm/s, P<0.0001) and marginally lower CFR (2.5±0.6 versus 2.6±0.6, P=0.044). Hyperemic coronary flow velocity did not differ between the 2 groups. By separate multiple linear regression analyses, after adjusting for sex, age, the highest systolic blood pressure tertile (≥140 mm Hg), left ventricular mass index, and cardiovascular risk factors, the highest PP tertile was associated with resting coronary flow velocity (P=0.003) and only marginally with hyperemic coronary flow velocity (P<0.02), whereas its association with CFR was not significant. CONCLUSIONS: In patients without epicardial coronary artery stenosis, the highest PP tertile is associated with an increased coronary flow velocity at rest.


Assuntos
Pressão Sanguínea/fisiologia , Circulação Coronária/fisiologia , Angina Pectoris/fisiopatologia , Velocidade do Fluxo Sanguíneo/fisiologia , Angiografia Coronária , Vasos Coronários/diagnóstico por imagem , Vasos Coronários/fisiologia , Ecocardiografia , Ecocardiografia sob Estresse , Feminino , Humanos , Hipertensão/fisiopatologia , Hipertensão/radioterapia , Masculino , Pessoa de Meia-Idade , Imagem Multimodal
17.
J Hypertens ; 34(6): 1201-7, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-27008173

RESUMO

OBJECTIVES: Little is known about the impact of pulse pressure on left ventricular systolic function. The aim of our study was to evaluate whether high pulse pressure is associated with subclinical left ventricular systolic dysfunction. METHODS: The study population included 143 participants (68 newly diagnosed, never-treated hypertensive, and 75 normotensive individuals) evaluated by echo-Doppler, including determination of global longitudinal strain (GLS) by speckle tracking. According to pulse pressure tertiles, participants were divided in two groups: the first group merging the first and second pulse pressure tertiles (n = 93, pulse pressure <55 mmHg) and the second group including the highest pulse pressure tertile (HPPT; n = 50, pulse pressure ≥55 mmHg). RESULTS: The two groups were comparable for sex, BMI, and heart rate, whereas age was higher in individuals with the HPPT (P < 0.0001). Left ventricular mass index was significantly higher in individuals with the HPPT (P < 0.01), with no significant difference in relative wall thickness. Among several indices of left ventricular systolic function, only GLS was lower in individuals with the HPPT (P < 0.001). Transmitral E/A ratio (P = 0.006) was lower and E/e' ratio higher (P < 0.001) in the HPPT group. By a multilinear regression analysis, HPPT (P < 0.020) and overweight (P = 0.025) were independent correlates of low GLS. Replacing HPPT with the highest systolic blood pressure tertile, GLS was independently associated with BMI (P = 0.040), but not with the highest systolic blood pressure tertile (P = 0.069). CONCLUSION: Elevated pulse pressure negatively influences left ventricular longitudinal mechanics in a mixed population of normotensive and untreated hypertensive individuals.


Assuntos
Pressão Sanguínea , Hipertensão/fisiopatologia , Disfunção Ventricular Esquerda/fisiopatologia , Adulto , Índice de Massa Corporal , Estudos de Casos e Controles , Ecocardiografia Doppler , Feminino , Frequência Cardíaca , Humanos , Hipertensão/complicações , Masculino , Pessoa de Meia-Idade , Sobrepeso/fisiopatologia , Sístole , Disfunção Ventricular Esquerda/diagnóstico por imagem , Disfunção Ventricular Esquerda/etiologia , Função Ventricular Esquerda
18.
Nat Commun ; 6: 8349, 2015 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-26391186

RESUMO

Many biological, social and technological systems can be described as complex networks. The goal of affecting their behaviour has motivated recent work focusing on the relationship between the network structure and its propensity to be controlled. While this work has provided insight into several relevant problems, a comprehensive approach to address partial and complete controllability of networks is still lacking. Here, we bridge this gap by developing a framework to maximize the diffusion of the control signals through a network, while taking into account physical and economic constraints that inevitably arise in applications. This approach allows us to introduce the network permeability, a unified metric of the propensity of a network to be controllable. The analysis of the permeability of several synthetic and real networks enables us to extract some structural features that deepen our quantitative understanding of the ease with which specific controllability requirements can be met.

19.
J Cardiovasc Med (Hagerstown) ; 14(12): 862-9, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23756415

RESUMO

Cardiac magnetic resonance (CMR) is commonly applied for the assessment of myocardial viability in patients with ischemic ventricular dysfunction, and it holds potential advantages over more traditional imaging modalities, including single-photon emission computed tomography (SPECT) and dobutamine stress echocardiography (DSE). CMR-based techniques for viability assessment include the evaluation of transmural extent of the scar using late gadolinium enhancement (LGE) images, the evaluation of end-diastolic wall thickness from resting cine images and the study of inotropic reserve during low-dose dobutamine infusion. During the past decade, the diffusion of the use of CMR for viability assessment confirmed the clinical strengths of this modality and, at the same time, helped to use old techniques with an increased level of awareness. With LGE CMR, both viable and nonviable dysfunctional myocardium can be visualized in a single image, allowing a direct quantification of the amount of regional viability, with a significant impact on the estimation of chance for recovery. As well, studies with CMR applied in the setting of ischemic heart disease allowed a better understanding of the best way to apply and interpret other tests for viability evaluation. For instance, it has been demonstrated that the transmural extension of the scar may influence the level of concordance between SPECT and DSE in assessing myocardial viability. The transmural extent of scar on LGE CMR also correlates with the timing of postrevascularization recovery of systolic function, with significant impact on the diagnostic accuracy of any applied imaging modality.


Assuntos
Imageamento por Ressonância Magnética/métodos , Isquemia Miocárdica/diagnóstico , Miocárdio/patologia , Meios de Contraste , Gadolínio , Humanos , Isquemia Miocárdica/patologia , Isquemia Miocárdica/fisiopatologia , Revascularização Miocárdica
20.
G Ital Cardiol (Rome) ; 14(7-8): 517-25, 2013.
Artigo em Italiano | MEDLINE | ID: mdl-23877549

RESUMO

Systemic inflammatory diseases are associated with increased cardiovascular morbidity and mortality. The link between inflammatory and cardiovascular diseases can be attributed to the coexistence of classical risk factors and inflammatory mechanisms activated during systemic inflammatory diseases involving the immune system. Unfavorable metabolic effects of anti-inflammatory drugs can also contribute to increase cardiovascular risk. Yet, clinical implications of these findings are not entirely clear, and deeper knowledge and awareness of cardiac involvement in inflammatory diseases are necessary. The aim of this review is to summarize cardiac involvement in systemic inflammatory diseases and to identify aspects where evidence is currently lacking that would deserve further investigation in the future.


Assuntos
Doenças Cardiovasculares/etiologia , Inflamação/complicações , Anti-Inflamatórios/efeitos adversos , Anti-Inflamatórios/uso terapêutico , Antirreumáticos/uso terapêutico , Artrite Reumatoide/complicações , Artrite Reumatoide/tratamento farmacológico , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/prevenção & controle , Doença das Coronárias/epidemiologia , Doença das Coronárias/etiologia , Humanos , Inflamação/tratamento farmacológico , Lúpus Eritematoso Sistêmico/complicações , Lúpus Eritematoso Sistêmico/tratamento farmacológico , Psoríase/complicações , Psoríase/tratamento farmacológico , Fatores de Risco , Escleroderma Sistêmico/complicações , Escleroderma Sistêmico/tratamento farmacológico , Fator de Necrose Tumoral alfa/antagonistas & inibidores
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